Thank you for stopping by the Weather Watch 12 blog! Big changes are looming for next week including an early winter plunge of cold, and the potential for rain, a wintry mix or snow! The sweeping changes will have a tropical influence, which sounds silly, but I'll explain if you keep reading.

Let's start with the first wintry change that occurs next week. Low pressure develops in the Plains and begins to lift northeast on Monday. This will pull moisture into the Midwest and result in rain, a wintry mix and snow. The big picture below shows the surface forecast map(courtesy WPC) at 7am Monday morning.

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Low pressure develops along the leading edge of arctic air spilling in from Canada. Picking out the rain/snow line will be tough, and the key to who see's measurable snow and who stays as a mix or rain. Another factor to consider is the 'warm' Lake Michigan water temperatures and a general easterly flow. This may boost temperatures a handful of degrees near the lake adding to the forecast complexity and increased chance of rain near the lake.

With such a fine line between snow, mix and rain models will be shifting around over the next several days. However, I want to show you one as an estimate of when the precipitation may arrive, and to show the issue with precipitation type.

The RPM forecast map below is valid at 6am Monday morning. Blue represents snow, pink mix and green rain. Most new model information that arrived Friday morning is trending the system a little farther north. This would mean more rain or mix in our area and less snow. I will keep close tabs on the trends/track of the storm all weekend here in the blog and on WISN 12 News this Morning 5-6/7-9am.

Behind the system early next week will be the coldest air of the season. The plunge of well below average temperatures will put an early winter feel in the air. The unseasonably cold airmass will be set in motion by an intense storm near Alaska in the Bering Sea. This system is actually the remnants of what was once Super Typhoon Nuri in the Pacific. A typhoon is another word for hurricane.

The map below shows the position of Nuri heading into today. I also labeled Alaska if you are not familiar with a map of the Pacific Ocean.

In the next 24 hours the storm is expected to undergo 'bombogenesis' or a rapid intensification. The strong low pressure system is labeled 'Nuri Storm'.

This powerful storm will help break down a block in our atmosphere which will in turn dislodge arctic air that spills south. The explainer map below courtesy of the NWS-Chicago shows the impact of the 'Nuri Storm' on our weather in the Midwest.

The early season cold snap will last most of next week. Highs will look to be in the 20s and 30s. Any locations that may see accumulating snow early in the week will likely be a few degrees colder each day as the snow likely sticks around.

One last note looking ahead...as I have discussed many times in the last several weeks the pattern supports a storm system in the Midwest around the end of November(Thanksgiving holiday weekend). Knowing this strong storm is in the Bering Sea, we can use the Bering Sea Rule to project forward around 20 days. This would put a warm-up in the Midwest ahead of the storm system, then rain or snow followed by much colder temperatures.

For the latest weather information watch WISN 12 News, and for updates throughout the day follow me on Twitter @jnelsonweather